2 * IOAPIC/IOxAPIC/IOSAPIC driver
4 * Copyright (C) 2009 Fujitsu Limited.
5 * (c) Copyright 2009 Hewlett-Packard Development Company, L.P.
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
13 * This driver manages PCI I/O APICs added by hotplug after boot. We try to
14 * claim all I/O APIC PCI devices, but those present at boot were registered
15 * when we parsed the ACPI MADT, so we'll fail when we try to re-register
19 #include <linux/pci.h>
20 #include <linux/module.h>
21 #include <linux/acpi.h>
22 #include <linux/slab.h>
29 static int ioapic_probe(struct pci_dev *dev, const struct pci_device_id *ent)
33 unsigned long long gsb;
34 struct ioapic *ioapic;
39 handle = ACPI_HANDLE(&dev->dev);
43 status = acpi_evaluate_integer(handle, "_GSB", NULL, &gsb);
44 if (ACPI_FAILURE(status))
48 * The previous code in acpiphp evaluated _MAT if _GSB failed, but
49 * ACPI spec 4.0 sec 6.2.2 requires _GSB for hot-pluggable I/O APICs.
52 ioapic = kzalloc(sizeof(*ioapic), GFP_KERNEL);
56 ioapic->handle = handle;
57 ioapic->gsi_base = (u32) gsb;
59 if (dev->class == PCI_CLASS_SYSTEM_PIC_IOAPIC)
64 ret = pci_enable_device(dev);
70 if (pci_request_region(dev, 0, type))
73 res = &dev->resource[0];
74 if (acpi_register_ioapic(ioapic->handle, res->start, ioapic->gsi_base))
77 pci_set_drvdata(dev, ioapic);
78 dev_info(&dev->dev, "%s at %pR, GSI %u\n", type, res, ioapic->gsi_base);
82 pci_release_region(dev, 0);
84 pci_disable_device(dev);
90 static void ioapic_remove(struct pci_dev *dev)
92 struct ioapic *ioapic = pci_get_drvdata(dev);
94 acpi_unregister_ioapic(ioapic->handle, ioapic->gsi_base);
95 pci_release_region(dev, 0);
96 pci_disable_device(dev);
101 static const struct pci_device_id ioapic_devices[] = {
102 { PCI_DEVICE_CLASS(PCI_CLASS_SYSTEM_PIC_IOAPIC, ~0) },
103 { PCI_DEVICE_CLASS(PCI_CLASS_SYSTEM_PIC_IOXAPIC, ~0) },
106 MODULE_DEVICE_TABLE(pci, ioapic_devices);
108 static struct pci_driver ioapic_driver = {
110 .id_table = ioapic_devices,
111 .probe = ioapic_probe,
112 .remove = ioapic_remove,
115 static int __init ioapic_init(void)
117 return pci_register_driver(&ioapic_driver);
119 module_init(ioapic_init);
121 MODULE_LICENSE("GPL");